A number of crispy, fat-fried food products have been developed as snack foods. However, these fat-fried products normally contain significant amounts of fat. For example, potato chips can have a fat content as high as 40%. Foods containing a large amount of fat require careful storage and the use of anti-oxidants to avoid having the product turn rancid upon contact with the atmosphere. In addition, a large amount of fat is a detriment in that it contributes a large amount of calories and diet-conscious people tend to avoid the use of such high-calorie-containing materials.
U.S. Pat. No. 2,863,770, incorporated herein by reference, describes a food product derived from edible tubers, such as potatoes, which is extruded under pressure and fried to give a crisp expanded product having the taste and aroma of a fried potato product, such as potato chips. More specifically, a pre-swelled potato flour containing between 30 and 40% water is extruded into strands. The strands are dried to a moisture content of between 6 and 10%. The dried strands are cut into piecelets, and the piecelets are fried in hot fat.
The frying expands the piecelets to about five times their original volume. U.S. Pat. Nos. 3,076,711 and 3,131,063, both incorporated herein by reference, are directed to related processes.
In U.S. Pat. No. 3,692,537, incorporated herein by reference, there is described a method of producing an expanded fried potato product from potato flour in which sugar content and the water-binding property can be simply and uniformly controlled. However, the resulting product is still a fat-fried product having the disadvantages discussed above.